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/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Posix rand_r function added May 1999 by Wes Peters <wes@softweyr.com>.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)rand.c 8.1 (Berkeley) 6/14/93";
#endif /* LIBC_SCCS and not lint */
#if 0
#include <sys/types.h>
#endif
#include <stdlib.h>
#ifdef TEST
#include <stdio.h>
#endif /* TEST */
static int
do_rand(unsigned long *ctx)
{
return ((*ctx = *ctx * 1103515245 + 12345) % ((unsigned long int)RAND_MAX + 1));
}
int
rand_r(unsigned int *ctx)
{
unsigned long int val = (unsigned long int) *ctx;
*ctx = do_rand(&val);
return (int) *ctx;
}
static unsigned long int next = 1;
int
rand(void)
{
return do_rand(&next);
}
void
srand(unsigned int seed)
{
next = seed;
}
#ifdef TEST
main()
{
int i;
unsigned myseed;
printf("seeding rand with 0x19610910: \n");
srand(0x19610910);
printf("generating three pseudo-random numbers:\n");
for (i = 0; i < 3; i++)
{
printf("next random number = %d\n", rand());
}
printf("generating the same sequence with rand_r:\n");
myseed = 0x19610910;
for (i = 0; i < 3; i++)
{
printf("next random number = %d\n", rand_r(&myseed));
}
return 0;
}
#endif /* TEST */
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